diff options
Diffstat (limited to 'block/genhd.c')
| -rw-r--r-- | block/genhd.c | 50 |
1 files changed, 49 insertions, 1 deletions
diff --git a/block/genhd.c b/block/genhd.c index 1a7659327664..f741613d731f 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -876,6 +876,20 @@ static void invalidate_partition(struct gendisk *disk, int partno) bdput(bdev); } +/** + * del_gendisk - remove the gendisk + * @disk: the struct gendisk to remove + * + * Removes the gendisk and all its associated resources. This deletes the + * partitions associated with the gendisk, and unregisters the associated + * request_queue. + * + * This is the counter to the respective __device_add_disk() call. + * + * The final removal of the struct gendisk happens when its refcount reaches 0 + * with put_disk(), which should be called after del_gendisk(), if + * __device_add_disk() was used. + */ void del_gendisk(struct gendisk *disk) { struct disk_part_iter piter; @@ -1514,6 +1528,23 @@ int disk_expand_part_tbl(struct gendisk *disk, int partno) return 0; } +/** + * disk_release - releases all allocated resources of the gendisk + * @dev: the device representing this disk + * + * This function releases all allocated resources of the gendisk. + * + * The struct gendisk refcount is incremented with get_gendisk() or + * get_disk_and_module(), and its refcount is decremented with + * put_disk_and_module() or put_disk(). Once the refcount reaches 0 this + * function is called. + * + * Drivers which used __device_add_disk() have a gendisk with a request_queue + * assigned. Since the request_queue sits on top of the gendisk for these + * drivers we also call blk_put_queue() for them, and we expect the + * request_queue refcount to reach 0 at this point, and so the request_queue + * will also be freed prior to the disk. + */ static void disk_release(struct device *dev) { struct gendisk *disk = dev_to_disk(dev); @@ -1727,6 +1758,13 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) } EXPORT_SYMBOL(__alloc_disk_node); +/** + * get_disk_and_module - increments the gendisk and gendisk fops module refcount + * @disk: the struct gendisk to to increment the refcount for + * + * This increments the refcount for the struct gendisk, and the gendisk's + * fops module owner. + */ struct kobject *get_disk_and_module(struct gendisk *disk) { struct module *owner; @@ -1747,6 +1785,13 @@ struct kobject *get_disk_and_module(struct gendisk *disk) } EXPORT_SYMBOL(get_disk_and_module); +/** + * put_disk - decrements the gendisk refcount + * @disk: the struct gendisk to to decrement the refcount for + * + * This decrements the refcount for the struct gendisk. When this reaches 0 + * we'll have disk_release() called. + */ void put_disk(struct gendisk *disk) { if (disk) @@ -1754,7 +1799,10 @@ void put_disk(struct gendisk *disk) } EXPORT_SYMBOL(put_disk); -/* +/** + * put_disk_and_module - decrements the module and gendisk refcount + * @disk: the struct gendisk to to decrement the refcount for + * * This is a counterpart of get_disk_and_module() and thus also of * get_gendisk(). */ |